Just my two cents to (a) add my endorsement to this video--it really
helped me understand all the new stuff with windowing, and therefore get
what I like; and (b) renew my observation that I'd really like a
"minimize" button on the viewer window, so I can set it to float, but then
can get it out of the way without closing it.

You can pin a viewer window if you want - which means it will shrink into a
tab when you are not using it. e.g. drag it/dock it on the side and then
pin it.

But, I am not sure why this is an issue - at least with my current
configuration, viewing windows show up on my bottom tool bar. So, I have a
viewing window open, I click on results, viewing window disappears, I click
on viewer and it comes back. In other words I can't minimize it, which I
suppose would be nice, but it gets covered up by other windows when I am
not using it.

After playing around with these windows a bit, I am glad there is a restore
factory defaults option. You can also save and load preferences - once
you've got things set the way you like, you may want to save them before
you start trying different things.

Getting back to Richard Campbell's question that started it all - I bet he
docked the command window in the middle and then couldn't find it, just
like the UCLA video shows. So, the next time he has that window visible,
dock it on the bottom or the sides. Or, maybe reset to factory
defaults. Once he has a setup he likes, save the preferences so he can get
that setup back if things ever get zapped again.